A federal government report released this week warns that protection of the 4,000-mile border between the United States and Canada is riddled with holes and the lack of security presents a greater terrorism threat than the porous U.S.-Mexico border.

The General Accountability Office studied four sections of the border, including the Detroit area, and concluded that in 2010 only 32 miles of the overall northern border — or less than 1 percent — “had reached an acceptable level of security.” That level means that all illegal border crossings were detected and an arrest was made.

In addition, the GAO found that the Border Patrol was aware of all illegal crossings on just 25 percent of the border.

The report, presented to Congress on Tuesday, immediately drew a sharp response from lawmakers.

“It is unacceptable to have such vulnerabilities along our northern border where we have only a handful of miles that are under operational control,” said Rep. Candice Miller, a Harrison Township Republican who chairs the House Subcommittee on Border and Maritime Security.

“To date, we are still waiting for the administration to put forth a detailed program to secure the border. We need to gain operational control of the entire border, both north and south, and I intend on holding a hearing which examines how the Border Patrol measures operational control of the border and how to improve our coordination of those efforts.”

The GAO cited a lack of coordination by the Border Patrol with state, local and Canadian law enforcement authorities. At the same time, the agency said it found that the approach to border security was plagued by too much overlap and redundancies.

The reported lack of Border Patrol effectiveness comes after the Department of Homeland Security had allocated $2.9 billion last year to secure the northern border. The GAO found that little progress has been made.

The Border Patrol reports to Customs and Border Protection, which works with Immigration and Customs Enforcement, or ICE. In turn, all those agencies are overseen by DHS.

More importantly, the report notes that the DHS has said that illegal crossings by terrorists or those smuggling terrorist weapons is greater on the Canadian border than on the southern border. That weakness is due to the large expanse of the northern border, in many cases through rural areas with a limited law enforcement presence, and the growing prominence of Islamic extremists in Canada.

According to officials, human traffickers operating in the area of Macomb and St. Clair counties charge approximately $1,500 to smuggle a person who is of Canadian or Caribbean descent. The prices range up to $3,000 for people from Europe or Asia.

“I have serious concerns that lack of coordination between Immigration and Customs Enforcement personnel and Border Patrol personnel is hindering border security in Detroit,” said Sen. Carl Levin, a Michigan Democrat. “Any failure to coordinate efforts between agencies that weakens security on the northern border is totally unacceptable. I have asked representatives from the Detroit offices of ICE and Customs and Border Protection to meet with me at my Detroit office within two weeks.”

A Border Patrol spokesman could not be reached for comment.

Levin serves as chairman of the Senate Permanent Subcommittee on Investigations. The GAO investigation was requested by Levin, Lieberman and three other senators.

The report studied four Border Patrol “sectors” — two in Washington state and Idaho, one in New England, and the Detroit sector, which actually includes an area that encompasses four Great Lakes states — Michigan, Illinois, Indiana and Ohio.

Much of the emphasis in the sprawling Detroit sector was on the Detroit area, though the report offered no specifics about weaknesses in border security on Lake St. Clair or the St. Clair River. The Border Patrol maintains a significant presence at Selfridge Air National Guard Base in Harrison Township.

The report recommends greater coordination and more resources, including technology that can provide high-tech policing of the border.

Last month, Customs and Border Enforcement announced that their unmanned Predator aircraft have expanded their capabilities. In their first long-range flight, the agency boosted their airspace along the northern border by 900 miles, completing an operation that began in the Lake-of-the-Woods region of Minnesota and ended near Spokane, Wash.

Miller has been pushing for Customs and Border Enforcement to fly unmanned aircraft out of Selfridge.

The Montreal Gazette reported on Wednesday that President Barack Obama and Canadian Prime Minister Stephen Harper are expected to give the green light Friday to a comprehensive shared review of border security.

The announcement will likely come at the White House after the two leaders hold a meeting touching on such topics as border security, the political unrest in Egypt and clean-energy initiatives, according to the newspaper.

The broad strokes of what will be considered by the two nations were revealed in a draft agreement leaked to the media in December.

The draft report notes that Canada and the U.S. share the largest and most integrated economic partnership in the world, with more than $550 billion in bilateral trade in goods and services in 2009.

The report also singled out the Windsor-Detroit crossings as a priority trade corridor, and urged the “expeditious implementation” of the Detroit River International Crossing bridge that’s proposed downriver from the Ambassador Bridge